//跨浏览器返回xml Dom 对象
function getXMLDOM(xmlStr) {
	var xmlDom = null;

	if(typeof window.DOMParser != 'undefined') { //w3c
		xmlDom = (new DOMParser).parseFromString(xmlStr, 'text/xml');
		var errors = xmlDom.getElementsByTagName('parsererror'); //得到解析错误标签的信息
		if(errors > 0) {
			throw new Error('手动抛出错误信息：' + errors[0].textContent);
		}

	} else if(typeof window.ActiveXObject != 'undefined') {
		//ie的不同版本
		var version = [
			'MSXML2.DOMDocument6.0',
			'MSXML2.DOMDocument3.0',
			'MSXML2.DOMDocument'

		];
		//循环判断支持哪个
		for(var i = 0; i < version.length; i++) {
			try {
				var xmlDom = new ActiveXObject(version[i]);

			} catch(e) {
				//错误跳过不处理
			}
		}

		xmlDom.loadXML(xmlStr);
		if(xmlDom.parseError != 0) {
			throw new Error('我的错误信息' + xmlDom.parseError.reason);

		}
		return xmlDom;
	} else {
		throw new Error('xmlDOM 对象');
	}

	return xmlDom;
}

//序列化xml兼容

function serializerXml(xmlDom) {
	var xml = '';
	
	if (typeof window.XMLSerializer != 'undefined') {
		xml = (new XMLSerializer()).serializeToString(xmlDom);
	} else if (typeof xmlDom.xml != 'undefined') {
		xml = xmlDom.xml;
	}
	
	return xml;
}